Casing element for excavation casing

ABSTRACT

A casing element for excavation casing wherein all of the elements thereof are interconnected by spot welding whereby the usual warping and twisting of similar casing elements due to conventional welding practices is eliminated. The sheets and spacer bars of the casing element are secured together and to the frame of the casing elements solely by spaced spot welds which do not thermally stress the casing elements sufficiently to effect warping and twisting thereof from a planar state.

United States Patent Krings [111 3,869,867 [451 Mar. 11, 19 75 1 CASING ELEMENT FOR EXCAVATION CASING 22 Filed: Aug. 10, 1972 211 Appl. No.: 279,302

[30] Foreign Application Priority Data Sept. 29, 1972 Germany 7136851 [52] [1.5. 61/41 A, 61/63 [51] Int. Cl. E2ld 5/06 [58] Field of Search 61/41 R, 41 A, 39, 39.1, 61/63, 49; 219/117 HD; 52/615 56] References Cited UNITED STATES PATENTS 1,091,905 3/1914 Zahner 52/620 X 2,481,046 9/1949 Scurlock 219/117 HD 2,766,855 10/1956 Johnson et al 52/620 X 2,915,150 12/1959 Weidler 52/620 X 2,926,761 3/1960 Herbert 219/117 HD 2,962,133 11/1960 Kivett et a1. 52/580 3,307,361 3/1967 Waterman 61/41 R l 1. I111 W G H1111] 3,416,322 12/1968 Bodine 61/39 X 3,496,727 2/1970 DeWeese et a1 61/41 A FOREIGN PATENTS OR APPLICATIONS 603,266 4/1926 France 61/49 1,186,605 8/1959 France 960,439 3/1957 Germany 1,123,988 2/1962 Germany 61/41 A Primary Examiner-Dennis L. Taylor Attorney, Agent, or Firm-Diller, Brown, Ramik & Wight [57] ABSTRACT 1 Claim, 3 Drawing Figures PATENTED MARI 1 i975 i I I I I i CASING ELEMENT FOR EXCAVATION CASING This invention relates in general to new and useful improvements in casing elements for excavations, and more particularly to a casing element which is formed of welded together metallic parts.

BACKGROUND OF THE INVENTION It is conventional to form casing elements of plates separated by Z-shaped bars. These bars are conventionally connected to the plates or sheets by continuous welded seams because of the thought heretofore that the casing elements must be severely rigidly secured together in order that they may have sufficient strength. It has also been found that when the casing elements are so welded together, they become dislocated due to the stresses from a large number of welded seams and the irregular thermal stressing which the welding imparts to the casing elements. The thermal stressing could be eliminated by subsequent annealing. However, this would require a disproportionately large outlay for apparatus and undesirable stress relieving times if the thermal stressing were to be eliminated.

It also has been found that no relief from the undue thermal stressing is obtained by interrupting the welded seams.

SUMMARY OF THE INVENTION It is now proposed to eliminate the problem of thermal stressing of the casing element in a manner which avoids the distortion. In accordance with this invention, the solution to this problem lies in that each casing element, which is formed from a shaped frame and a filling disposed therein, has a filling which is formed by a pair of parallel sheet plates, and between them as spacers, spacer bars, which may be for example of a Z, H or U configuration, which spacer bars are joined to sheet plate only by spot welding.

The casing element formed in accordance with the foregoing, because of the slight thermal stressing and spot welding, is not only substantially free of stress, but in addition to the more rapid, simpler and cheaper manufacture, also offers the advantage that it has smooth outside walls that favor sliding relative to the ground.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing:

IN THE DRAWING:

FIG. I is a fragmentary elevational view of a casing element in accordance with the invention.

FIG. 2 is atop view of FIG. 1.

FIG. 3 is a transverse sectional view taken along the line Ill III of FIG. 1.

The casing element shown in the drawings consists essentially of two lateral slide bars 1 (of which only one is illustrated) which can be introduced into corresponding hollow posts (not shown), and which are rigidly connected by means ofconnecting members 2 with a frame or edge 3 of the primary portion of the casing element, said frame surrounding the primary portion of the casing element and being formed of U-shaped parts.

In order that the casing element may be of a rigid configuration and retain substantially the planar condition at all times, the connection between the slide bars 1 and the frame 3 is reinforced by a plurality of vertically spaced connecting plates 7 which are suitably welded to the slide bars 1, the frame 3 and the adjacent connecting member 2.

Frame 3 is fixedly connected with a filling, generally identified by the numeral 4, which filling consists of parallel sheet plates 5 and, between these. bars serving as spacers, which spacers selectively have a Z, H or U profile. It is to be noted that the spacer bars 6 have been illustrated as being of a U-cross section and are vertically spaced between the plates 5.

It is to be particularly noted that the plates 5 are welded to the bars by spot welding 8. The filling 4 can also be secured to the frame 3 by spot welding, such as spot welding 9.

The spot welding connections are completely adequate for the operational requirements and have the effect that the casing elements can be made entirely work distortioned free. Moreover, the resultant casing element has smooth side walls so that penetration of the casing element into the ground or the withdrawal thereof offers no difficulties whatsoever. Further, because of the lack of deterioration of any finish which may be applied to the plates 5 as would normally occur with seam welding, the casing element is substantially corrosion resistant. Finally, the warp-free construction of the casing element makes it possible for a smooth setting up, one on the other, ofa plurality of easing elements. of course, the warp-free casing element also permits the slide bars 1 to be readily inserted within the associated hollow post in that the slide bars 1 have a constant angular relationship with respect to the planar casing element.

Although only a preferred embodiment of the casing element has been specifically illustrated and described herein, it is to be understood that the casing element may be formed of a slightly different arrangement of plates and bars without departing from the spirit and scope of the invention, as defined by the appended claims.

I claim:

l. A new article of manufacture comprising a casing element for excavation casing including a frame formed of shaped structural members of a class including channel members, and filling comprising a plurality of spacers extending between and rigidly secured to said frame structural members, said spacers being in the form of shaped elements, and a pair of metal sheets mounted on both sides of said frame and having disposed therebetween said spacers, the casing element being improved by the securement of said sheets to said frame and said spacers solely by a plurality of spot welds which render the casing element free of distortions due to thermal stresses, at least one edge of said frame having a post member secured thereto in spaced relation by means of connecting members, the connection between said frame and said post member being reinforced against movement of said casing element from a generally planar state, said connection between said post and said frame including further structural members extending generally coextensive with said post and rigidly secured to both said post and said frame, said structural members being spaced transversely of said posts and generally within the thickness of said frame, and there being reinforcing elements spaced along the length of said post and lying in transverse planes, said reinforcing elements being rigidly secured to said post, at least one of said further structural members and said frame. 

1. A new article of manufacture comprising a casing element for excavation casing including a frame formed of shaped structural members of a class including channel members, and filling comprising a plurality of spacers extending between and rigidly secured to said frame structural members, said spacers being in the form of shaped elements, and a pair of metal sheets mounted on both sides of said frame and having disposed therebetween said spacers, the casing element being improved by the securement of said sheets to said frame and said spacers solely by a plurality of spot welds which render the casing element free of distortions due to thermal stresses, at least one edge of said frame having a post member secured thereto in spaced relation by means of connecting members, the connection between said frame and said post member being reinforced against movement of said casing element from a generally planar state, said connection between said post and said frame including further structural members extending generally coextensive with said post and rigidly secured to both said post and said frame, said structural members being spaced transversely of said posts and generally within the thickness of said frame, and there being reinforcing elements spaced along the length of said post and lying in transverse planes, said reinforcing elements being rigidly secured to said post, at least one of said further structural members and said frame. 